Projection device with automatic spot correction

Abstract

A projection device with automatic spot correction includes an image generation unit, a light sensor, and a controller. The image generation unit outputs a light beam to scan to generate an image. The light sensor senses the light beam to obtain a spot position formed on the light sensor. The controller is coupled to the image generation unit and the light sensor. When executing an automatic spot correction procedure, the controller calculates an offset value of the spot position and uses an adjustment mechanism to correct the spot position.

What is claimed is: 
     
         1 . A projection device with automatic spot correction, comprising:
 an image generation unit outputting a light beam to scan to generate an image;   a light sensor sensing the light beam to obtain a spot position formed on the light sensor; and   a controller coupled to the image generation unit and the light sensor, with when executing an automatic spot correction procedure, the controller calculating an offset value of the spot position and using an adjustment mechanism to correct the spot position.   
     
     
         2 . The projection device of  claim 1 , wherein the projection device further comprises a housing and a transparent cover, with the housing having an opening, with the transparent cover covering the opening; and wherein the image generation unit and the controller are disposed in the housing, with the light sensor disposed on the transparent cover. 
     
     
         3 . The projection device of  claim 1 , wherein the projection device further comprises a beam splitter inserted in a traveling path of the light beam, with the beam splitter splitting the light beam to obtain an auxiliary light beam traveling along an auxiliary path; and wherein the light sensor is inserted in the auxiliary path. 
     
     
         4 . The projection device of  claim 1 , wherein the image generation unit comprises a plurality of colored light sources and a scanning mirror, with each of the plurality of colored light sources outputting the light beam to the scanning mirror to scan to generate the image. 
     
     
         5 . The projection device of  claim 4 , wherein the adjustment mechanism includes: the controller sequentially enabling the plurality of colored light sources to obtain the spot position of the light beam outputted by each of the plurality of colored light sources; based on the spot position corresponding to one of the plurality of colored light sources, calculating the offset value of the spot position corresponding to each of the others of the plurality of colored light sources; and, controlling the scanning mirror to correct the spot position according to the corresponding offset value. 
     
     
         6 . The projection device of  claim 4 , wherein the adjustment mechanism includes: the controller sequentially enabling the plurality of colored light sources to obtain the spot position of the light beam outputted by each of the plurality of colored light sources; based on a default spot position, calculating the offset value of the spot position of the light beam outputted by each of the plurality of colored light sources; and, controlling the scanning mirror to correct the spot position according to the corresponding offset value. 
     
     
         7 . The projection device of  claim 4 , wherein the plurality of colored light sources comprise a red light source, a green light source, and a blue light source. 
     
     
         8 . The projection device of  claim 4 , wherein the scanning mirror comprises a micro-electro-mechanical-systems (MEMS) scanning mirror. 
     
     
         9 . The projection device of  claim 1 , wherein the automatic spot correction procedure is automatically executed during an initialization process when starting the projection device. 
     
     
         10 . The projection device of  claim 1 , wherein the automatic spot correction procedure is manually executed by operating a user interface when the projection device works normally.